NGC 6217
Galaxy in the constellation Ursa Minor
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NGC 6217 is a barred spiral galaxy located some 67 million light years away,[3] in the constellation Ursa Minor. It can be located with a 10 cm (4 in) or larger telescope as an 11th magnitude object about 2.5° east-northeast of the star Zeta Ursae Minoris.[4] The galaxy is inclined by an angle of 33° to the line of sight along a position angle of 162°.[3]
| NGC 6217 | |
|---|---|
NGC 6217 imaged by the Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Ursa Minor |
| Right ascension | 16h 32m 39.217s[1] |
| Declination | +78° 11′ 53.56″[1] |
| Redshift | 0.004543 ± 0.000013[2] |
| Heliocentric radial velocity | 1,368[3] km/s |
| Distance | 67.2 Mly (20.6 Mpc)[3] |
| Apparent magnitude (V) | 11.2[4] |
| Characteristics | |
| Type | (R)SB(rs)bc[5] |
| Apparent size (V) | 55,000 light years |
| Other designations | |
| ARP 185, UGC 10470[2][6] | |
A morphological classification of (R')SB(rs)bc[5] indicates that NGC 6217 has a false outer ring-like structure formed from the spiral arms (R'), a well-defined bar running across the nucleus (SB), a partial inner ring (rs), and moderately-wound spiral arms (bc).[7] The nucleus is spherical in shape, showing no indication of oblateness.[5] The prominent bar spans an angular distance of 48″ (48 arc seconds) across the galaxy along a position angle of 35.97° ± 0.35°. At 10″ southeast of the nucleus is a prominent region of star formation. The inner ring is about 43″.5 across.[8]
NGC 6217 has been characterized as a starburst galaxy, which means it is undergoing a high rate of star formation compared to a typical galaxy. As a result, the spectrum is dominated by stellar photoionization from young, hot stars.[9] This component is less than 10 million years old, producing a blue-hued spectral continuum with absorption weak lines from elements other than hydrogen and helium.[6] At the core of the galaxy is a low-luminosity active galactic nucleus which has formed an H II region.[10]
Supernova
One supernova has been observed in NGC 6217: SN 2018gj (Type II, mag 14.6) was discovered by Patrick Wiggins on 14 January 2018.[11]
